Question for the numbers guy(s)

RickySteve · 07-04-07, 11:50 PM

Very slight relationship. Nowhere near being valuable.

Ganchrow · 07-05-07, 12:02 AM

Originally posted by Dark Horse

Do games with RF/HD (road faves/home dogs) show an edge towards the over, and games with HF/RD towards the under?

The RF/HD game should have a bottom of the 9th more often than the HF/RD game, so the extra 1/2 inning should produce more runs.

Just wondering if the percentages are known.

From the 1999 - 2006 seasons and using covers.com historical da, there were 18,992 games where one team was favored over the other.

Of the 11,017 games in which the home team was favored, the game went over 46.46% of the time, went under 48.86% of the time, and pushed against the total 4.67% of the time.

Of the 7,975 games in which the road team was favored, the game went over 47.39% of the time, went under 48.18% of the time, and pushed against the total 4.43% of the time.

Dark Horse · 07-05-07, 01:40 PM

Thanks for looking that up. Nothing there.

Dark Horse · 07-05-07, 07:13 PM

Got another one. Baseball will do that to you.

What, apart from wind, decides if a ball travels well through the air or not? Is it temperature or air thickness, or something else? And how do you measure it?

The HG · 07-05-07, 07:24 PM

Originally posted by Dark Horse

Got another one. Baseball will do that to you.

What, apart from wind, decides if a ball travels well through the air or not? Is it temperature or air thickness, or something else? And how do you measure it?

I'll answer this in one second. It is an important thing to consider in baseball, both for totals and for sides.

The HG · 07-05-07, 07:31 PM

Originally posted by Dark Horse

Got another one. Baseball will do that to you.

What, apart from wind, decides if a ball travels well through the air or not? Is it temperature or air thickness, or something else? And how do you measure it?

Air pressure is a key factor. At higher elevations, air has a lower density, which makes balls carry better, because the so-called "drag" is reduced (about 3 percent for every additional feet of elevation). That's a key factor in why Coors had such high totals when it first opened (at 5,000 feet, balls hit at Coors experience on average about 16 percent less drag than balls hit in stadiums at sea level). Lower air pressure reduces the friction of the air against the ball. Weather also influences air pressure at any given time. When they talk about a "low pressure system" or a "high pressure system" in the area, that will have an effect on the air pressure in the stadium.

Warm air also makes balls carry better, because warm air expands and reduces air density.

Higher humidity will also help balls carry better, because the air becomes less dense, but this factor is not too important compared to the others. With humidity at 80%, air density only goes down 1% compared to dry air at the same temperature and pressure.

Finally, the spin of ball after it is hit affects how far it travels, which is partly why some pitchers give up more home runs than others.

Dark Horse · 07-05-07, 07:41 PM

Thanks!

Does that mean the ball travels farther in tropical conditions (warm and humid)? Just asking, because I have a hard time picturing that.

Do you know any websites that have this info -live- for baseball stadiums?

The HG · 07-05-07, 07:57 PM

Originally posted by Dark Horse

Thanks!

Does that mean the ball travels farther in tropical conditions (warm and humid)? Just asking, because I have a hard time picturing that.

Yes, but not if the tropical conditions exist at lower altitudes. Coors of course is not tropical at all, but the ball carries there because of the altitude.

It is a bit counter-intuitive to think that humidity makes air less dense, since humidity seems like it is "adding" something to the air - moisture. But the water molecules are actually replacing other molecules - nitrogen and oxygen - which are heavier than water. The moisture in the air displaces heavier elements, making the air "lighter" overall. But again, humidity isn't a huge factor, although it's not insignificant.

Dark Horse · 07-05-07, 08:12 PM

That's the counter-intuitive part. Oxygen is being replaced by water, so it's harder to breathe. We get tired, but the ball doesn't.